diff --git a/theme/classic.html b/theme/classic.html
index 2c8686e..897a7d3 100644
--- a/theme/classic.html
+++ b/theme/classic.html
@@ -852,6 +852,7 @@
 <!--GuestStart-->
             function getext(str) {
                 strarry=str.split('.');
+                if (strarry.length==1) return '';
                 ext=strarry[strarry.length-1].toLowerCase();
                 var reg = new RegExp(".","g");
                 var a = str.replace(reg,"");